Eerie Gatekeeper

Whenever another creature you control enters
the battlefield under your control, Molten
Gatekeeper deals 1 damage to each
opponent.
Unearth {r} ({r}: Return this card from your
graveyard to the battlefield. It gains haste.
Exile it at the beginning of the next end step or
if it would leave the battlefield. Unearth only
as a sorcery.)